Sheet-mounting device



p 1930. w. H. THOMSON 1,775,742

SHEET MOUNTING DEVICE Filed April 24. 1929 INVENTOR 2., fifiamxsww wATTORNEY Patented Sept. 16, 1930 Y UNITED STATES PATENT OFFICE] WILLIAMHAROLD THOMSON, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOB TO AMERI- CANTELEPHONE AND TELEGRAPH COMPANY, A CORPORATION OF NEW YORK SEEET-MOUNTING DEVICE Application filed April 24,

mounting sheets of material upon a cylindrical surface in a definitemanner.-

In, the operation of mounting sheets of flexible material uponcylindricaldrums, for example, in connection with picture transmissionequipment employing revolving picture drums, a recording film or blankis mounted upon a reproducing drum during the reproducing-process. Th1soperation requires changing the record film or blank for each picture.The mountinspreviously em: ployed have been found di cult to manipulate,time consuming in adjustment and unreliable in maintenance.

One of the objects of the present invention is to facilitate andsimplify the attachment of a sheet of flexible material or film to acylindrical drum.

Another object is to hold such sheet of flexible material or film on thedrum in a secure and reliable manner.

In one embodiment'of this invention, the opposite sides of a lightsensitive record blank or film are held by clamping strips whichregister. with grooves in the reproducing drum of a picture transmissionequipment when the film is wrapped arolfiid the drum. The film is thenheld under tension by spring elements so arranged that they tend topdrawand maintain the clamping means'together. The removal and replacemnt ofrecording films is thus reduced to a very simple operation. Y

Thenovel features which are considered characteristic of-this inventionare-set forth with particularity in .the appended claims. Theinvention,both as to its organization andmethod of operation, togetherwith otherobjects and advantages thereof, will' be further explained in thefoll'owingdetailed description having reference to t e accomfigures: a

Figure 1 is a side elevation of a picture reproducing drum and filmmounting device according to this invention.

Fig. 2 is an exploded view inperspective of the two clamping strips andassociated panying drawing consisting of the following,

resilient members15 are adapfed to 1929. Serial 1%. 357,741.

elements, and the film whose edges are to be held by such strips. J,

Fig. 3 is a sectional view of the drum on line 33 of Fig. 1 adjacent tothe button 20.

In the embodiment ofthe invention shown in the drawing, the reference 5designates a reproducing drum. This drum, as well knownin the art, maybemounted on a shaft suitably supported so that it may be rotated, andoperated in a well understood manner. The drum has a light sensitiverecord blank or film 6 mounted on a cylindrical surface'7 which has alongitudinal groove 8 cut therein,

The edges ofth'e film are respectively-clamped between the strip 9 andthe strip 10. Each clamping strip consists of an upper and lowerparallel, metallic member, and the upper member may have one of itsedges upturned to increase its rigidity. The lower members of each stripregister with the longitudinal groove 8. The upper and lower parallelmembers of the strips 9 and 10 are adapted to be clamped together bymeans of screws 11 which pass through holes in the lower member- 0L eachstrip and screw into the threaded holes of the companion upper member ofthe strip. These screws may be provided with enlarged or knur led headsso that they are easily operated by hand. These enlarged heads enterslots 12 provided through the longitudinal groove 8 and extend towardthe center of the drum, when the clamping strips .9 and 10are inposition. I

Holes 13 are provided ear the ends of the clamping strip ,10 andregister with pins 14 which extend from the surface 7 of the drumthrough said holes. The clampin" strip and drum thus provide co-actingmem rs which serve to self-center the clamp and thereby fix the positionthereof as well as the position of the film 6. Y

The clamping strip 9 is' provided with hook-shaped resilient members 15which have one of their ends abutting the upturned portions of,saidstrip and are suitably aflixed to .the surface thereof, The other endsof the hook members 15 may be inturned to form knobs which may be easilygras d. The sprung over the lugs 17 carried y the opposite clampingstrip and engage with the recessed portions of the lugs in latchedconnection. a This latched connection serves to draw the film 6 tightlyin position about the drum.

drum. This connection serves to center the strip 9 and position it inalignment with the companion strip 10.

auxiliary connection may be provided tocooperate with the latchedconnection above mentioned. This auxiliary connection may be providedwith a button 20 which is flexibly mounted in any desired manner-so thatthe button may be lifted and rotated to turn over the adjacent edges ofthe clamping 7 strips 9 and 10 to hold them firmly in position on thedrum.

In the application of the film to the drum, one edge of the film ispositioned between one clamping strip, and an opposite edge positionedbetween the other clamping strip. The film is then wrapped about thedrum so that the clamping strips register with the longitudinal groovein the drum, with the heads of the screws extending toward the center ofthe drum through the slots. When the clamping strips-are in thisposition, the resilient hook members on one strip are latched over thelugs of the opposing strip to tension the film and hold it in adesirable relationship to the drum surface.

o By means of the present invention a simple and reliable arrangement isprovided for holding the film on the drum. The clamps are quicklyremovable from the drum and plied thereto,

from the film, thus effecting a large saving in time by the use of thisdevice.

While there is shown and described herein one preferred form of theinventionby way of illustration, it is understood that it is not limitedor confined to the precise details of construction herein described anddelineated, as modification and variation may be made within the scopeof the appended claims without departing from the spirit of theinventlon.

What is claimed is:

1. A sheet mounting device comprising a drum, a sheet to be mounted onsaid drum, a removable clamp for one edge of said sheet, said clamp andsaid drum having co-acting members for fixing the position of the clampand thereby fixing the edge of the sheet with respect to the drum whenthe clamp is apa second clamp for the oppo- Slt edge of said sheet,hook-shaped resilientengagmg members fixed upon said latter clamp, andlugs upon said first mentioned clamp over which said resilient-engagingmembers may be sprung to draw the sheet tight upon the drum.

2. A sheet mounting device comprising a drum, a sheet to be mounted onsaid drum, a I

removable clamp for one edge of said sheet, said clamp and said drumhaving co-acting members for fixing the position of the clamp andthereby fixing the edge of the sheet with respect to the drum when theclamp is applied thereto, a second clamp for the opposite-edge of saidsheet, hook-shaped resilient-engagmg members fixed upon said latterclamp and lugs upon said first mentioned clamp having recessed portionstherein in which said resilient-engaging members may be latched to drawand maintain the sheet tight upon the drum, and means for centering oneedge of the sheet to position it in alinement with the opposite edge ofsaid sheet.

3. A sheet mounting device comprising a drum, a sheet to be mounted onsaid drum, a removable clamp for one edge of said sheet, said clamp andsaid drum having co-acting members for fixing the position vof the clamand thereby fixing the edge of the sheet with respect to the drum whenthe-clamp is applied thereto, a second clamp for the opposite edge ofsaid sheet, hook-shaped resilient-engaging members fixed upon saidlatter clamp, lugs upon said first mentioned clamp over which saidresilient-engaging members may be sprung to draw the sheet tight uponthe drum, and a button flexibly attached to said drum, said button beingadapted to lift and turn over the edges of said clamps to maintain themfirmly in position on the drum.

In. testimony whereof, I have signed my name to this specification this18th day of April, 1929. WILLIAM HAROLD THOMSON.

